Over the past decade, the demand for strong, light-weight materials has led to the increasing use of fiber reinforced composites for a variety of applications. For example, composites are often used as structural materials in airframes or for various components in gas turbine engines. Fiber reinforced composites typically comprise a plurality of fibers dispersed in a continuous matrix. Depending on the application, the matrix may be a polymer, a metal, a metalloid, a glass, a glass-ceramic, or a ceramic. Polymer matrices are usually used for lower temperature applications, while metal, metalloid, glass, glass-ceramic, and ceramic matrices are typically used for higher temperature applications. Glass-ceramic and ceramic matrices often are useful at temperatures up to and above those allowable for metal matrices. Regardless of the application, the increasing use of composite materials has created a need to join adjacent, non-coplanar composite panels and structures to form complex shapes.
Although several techniques are available for joining polymer matrix composite structures, relatively few methods for joining metal, metalloid, glass, glass-ceramic, and ceramic matrix composite structures exist. Many of the existing techniques for joining metal, metalloid, glass, glass-ceramic, and ceramic matrix composite structures rely on bonding adjoining matrices to each other. Because such joints provide a bond only between the matrices, however, they typically have the characteristics of an unreinforced metal, metalloid, glass, glass-ceramic, or ceramic. As a result, such joints can be considerably weaker than the base composites themselves and can be unsuitable for many applications.
Therefore, what is needed in the industry is an improved method for joining fiber reinforced composite structures, particularly those made with glass, glass-ceramic, or ceramic matrix fiber reinforced composites.